By Jim Devries and Lee Moats
Dropping from a crisp blue sky, a pair of northern pintails swoop low over golden wheat stubble recently emerged from a winter's snowy blanket. A brilliant April morning sun glints off distant sheetwater as the pair bank and gain altitude before separating. The drake doesn't hesitate, but wings purposefully to a distant wetland to wait. The hen, wings cupped, settles quickly to the ground between arrow-straight rows of grain stubble. She remains motionless, head erect, for what seems an eternity. Satisfied her landing has gone unnoticed by any lurking predator, she slowly lowers her head. Adopting a sneaky, ground-hugging posture, she waddles slowly through the stubble, stopping occasionally to scan the sky. Seventy feet from her landing spot, she stops. With an economy of motion, she parts a thick layer of down to uncover eight eggs in a shallow bowl scraped from the earth. She settles onto her nest and becomes virtually invisible against the background soil.
The stage for destruction has been set. In a week, spring field cultivation will leave nothing behind except freshly tilled soil and a scattering of eggshells.
The Prairie Pothole Region (PPR), the cradle of North American waterfowl production, has changed and, with it, the fortunes of many duck populations. Grassland plains and rolling parklands dotted with innumerable wetlands, once vast in extent, have largely been replaced with landscapes dominated by cropland and tracked by drainage. In much of the Canadian PPR, up to 80 percent of the landscape is cultivated annually (about 66 million acres in 2001). While some ducks, especially pintail, will nest in croplands, these lands are generally avoided by nesting ducks. Typical waterfowl nesting sites in grassy clumps or brushy thickets are limited primarily to remnant lands that have survived cultivation, such as road ditches, fence lines, some wetland margins, and lands unsuitable for cultivation. These same lands are what remain as habitat for many songbirds, small mammals, and insects. Predators also have adapted to the evolving landscape and have learned the value of these remnant habitats as profitable foraging areas. As a result, waterfowl nest survival has declined in recent history to where, in many landscapes, fewer than 10 percent of nests survive to hatch.
While spring tillage and predation are the immediate causes of nest destruction, changes in habitat and farming practices on the prairie landscape are what drive the productive potential of the PPR. Hence, the fortunes of the waterfowl resource rest with a large-scale investment in habitat and alternative farming practices that persist on the land and provide safe cover for nesting hens. Indeed, the impact of large-scale habitat restoration on waterfowl production can be seen in the tremendous rebound of duck populations in the Dakotas following the return of grass to the U.S. prairies under the federal Conservation Reserve Program (CRP). While Ducks Unlimited (DU) is aggressively promoting a federal CRP-style program in the two-thirds of the PPR that falls in Canada (see "Canada Launches Conservation Cover Program" in the Sept/Oct 2002 issue), that alone may not be sufficient to turn the fortunes of nesting ducks. This is where fall-seeded crops like winter wheat come in.
With the exception of fall-seeded rye, spring-seeded crops have always been the norm in the Canadian portion of the PPR. Crops such as spring wheat, barley, and canola currently dominate the acres sown each April and May. Winter annual crops, such as winter wheat and fall rye, are planted in August or September on the Canadian prairies. These crops germinate prior to freeze-up, lay dormant over the winter months, and continue growth in the spring. Widespread adoption of winter annuals has generally been limited, however, by the availability of cold-tolerant varieties, grain markets, and farming traditions. Nevertheless, the fact that fall crops remain undisturbed by tillage during the April-July nesting season has induced DU staff to promote fall crops as a potentially productive nesting habitat.
But how beneficial are fall-seeded crops for nesting ducks? Quantifying the use of any cropland habitat by nesting ducks has always been problematic. Farmers, understandably, are less than enthusiastic about the traditional nest searching techniques used by waterfowl researchers to quantify nest densities and nest success. For this reason, in more than 50 years of waterfowl research in the PPR, waterfowl nesting in croplands has never been studied with the same effort as in surrounding habitats.
At least, that's the way it was until 1996, when DU initiated four years of research to document waterfowl nesting in spring- and fall-seeded crops in Saskatchewan. This effort was undertaken to determine the value of a DU program called Conserve and Win that introduced farmers to growing winter wheat. In the fall of 1995, DU staff planted 1,109 acres of fall rye and winter wheat near Yorkton, Saskatchewan, on cropland DU had recently purchased for conversion to perennial nesting cover. Between May and July 1996, staff from DU's Institute for Wetland and Waterfowl Research (IWWR) searched these crops four times to locate waterfowl nests by dragging a 150-foot rope through the crop between two ATVs. As the rope passed over nests, sitting hens would fly off, allowing researchers to pinpoint the nests' location. Nests were then checked every seven days until they either hatched or were destroyed by predators.
The results of the study were encouraging. A total of 111 duck nests—an average of slightly more than one nest for every 10 acres—was found. That number was surprising because it was much higher than previous estimates of waterfowl nest density in cropland. As well, researchers know that not every nest is found, so, this was undoubtedly an underestimate. Six different species of ducks made their nests in the winter cereals, including mallard, blue-winged teal, green-winged teal, gadwall, northern shoveler, and northern pintail. And another surprise was in store—approximately 20 percent of the nests survived to hatch—double the nest success in many habitats. The research was repeated in 1997, with the objective of comparing fall-seeded crops to conventional spring-seeded crops. Again, nest densities averaged around one nest every 10 acres in the fall-seeded fields. Only one nest every 44 acres was found in spring-seeded fields, however. More than 20 percent of nests hatched in both crop types.
Because northern pintails nest readily in crop stubble, further research concentrated on determining the potential value of fall-seeded crops to nesting pintails. In late summer 1997 and 1998, DU staff began working with more than 23 different grain producers on two study sites in the heart of pintail country in southern Saskatchewan (see map on page 45). Each year, approximately 2,000 acres of rye and winter wheat were fall-seeded specifically for the pintail study. In addition, agreements were negotiated to allow an equal acreage of spring-seeded wheat and barley to be searched. Over the two years, one nest was found in every nine acres of fall-seeded crop, of which 30 percent were pintails. One nest was found in every 74 acres of spring-seeded crop, and 60 percent of these were pintails. Nest success averaged 22 percent in the fall-seeded crop but only 3 percent in the spring-seeded crop.
Based on the research results, DU has concluded that the potential of fall-seeded crops to improve the fortunes of prairie-nesting ducks, especially pintails, is great (see "Winter Wheat and the Future of Pintails" sidebar). The research clearly indicates fall-seeded croplands are much more attractive to nesting ducks than spring-seeded croplands, likely due to the much earlier crop growth and hence better vegetative cover during the nesting season. More importantly, nest survival is consistently higher than often found in other habitats in the landscape, due in part to the absence of spring tillage. The greatest potential advantage is that, unlike many promoted conservation practices that exclude the agricultural use of the land, winter wheat is a profitable commodity with the potential to cover many of the traditionally cropped acres in the PPR.
Although DU has demonstrated the value of fall-seeded crops over spring-seeded crops for nesting waterfowl, the largest challenges remain ahead. Western Canada has an established tradition of growing short-season spring-seeded crops, which dominate cultivated land. DU's goal is to change cropping practices on the Canadian prairies so that winter wheat replaces a majority of the spring wheat. Creating that magnitude of change—there are about 21 million acres of spring wheat in Prairie Canada—is no easy task, however. It requires an understanding of the industry, crop production practices, policies that regulate the industry, and the producers who grow the crops. DU has responded to this challenge by developing expertise in winter wheat production, and in developing strategies to accomplish landscape-level change.
For winter wheat to replace spring wheat in western Canada, two elements are required. First, producers will need to realize an economic advantage to growing winter wheat, compared to alternative crops. Second, producers and the agricultural industry in Prairie Canada will need to change their focus from traditional crop rotations to rotations that include winter wheat. Facilitating these changes is the focus of DU's winter wheat strategy. The strategy is based in part on the experience gained through early work with farmers in the 1990s, which showed that winter wheat can be produced consistently and successfully, but only if specific production practices are followed. Improved varieties are essential to make winter wheat more competitive and profitable for farmers. It will also require a mental shift away from spring-seeded crops to fall-seeded crops.
Weather is the key to the economics of winter wheat production. Winter wheat, as the name implies, needs to survive the winter—and western Canadian winters can be very severe. Winter survival depends on the cold tolerance of the variety and the production practices of the farmer growing the winter wheat. Probably the most important component of DU's winter wheat strategy is developing superior varieties that have improved cold tolerance, yield, quality, and disease resistance. To this end, DU has partnered with winter wheat breeders at the University of Saskatchewan in Saskatoon and at Agriculture and Agri-Food Canada's crop research station near Lethbridge, Alberta. The partnership with the University of Saskatchewan seeks to gain a better understanding of cold tolerance in winter wheat and to develop more cold-tolerant varieties (see "New Varieties: The Key to Winter Wheat Expansion" sidebar at right). The partnership with Agriculture and Agri-Food Canada focuses on disease resistance.
Winter wheat profitability depends not only on being able to produce the crop, but on the market opportunities as well. To address this need, DU has partnered with producer groups such as the Alberta Winter Wheat Producers Commission and Winter Cereals Canada to support their efforts in developing improved markets for winter wheat and to work toward changing regulations and policies that inhibit winter wheat expansion.
A change in traditional production practices also needs to occur. Planning for seed planting in September, seeding shallow, and seeding into standing stubble are essential for winter survival and for high yield. Standing stubble works as a snow trap, keeping an insulating blanket of snow on the soil surface. Soil warmth ensures the winter wheat seedlings survive despite extremely cold air temperatures. Helping producers understand and follow the "recipe" for success has been another key part of DU's strategy through the delivery of an extension program that includes a winter wheat production manual containing comprehensive production information. Other extension programs include "Train the Trainers," a program aimed at agricultural professionals in agribusiness and government who can promote winter wheat and advise producers on its production. Further, a core grower program focuses on developing an effective group of producer advocates who promote the crop to their neighbors and help them learn the key production practices. Demonstration and incentive programs are used to help growers get into the practice of growing winter wheat. DU is also seeking the help of agribusinesses to promote winter wheat, and will work hard to enlist the help of governments through Canada's recently developed federal agricultural policy framework.
DU has made progress in expanding winter wheat acreage in western Canada, and the prospect of future advances is good. We are one step closer to landscapes that are productive for both ducks and people.
A late May breeze ripples across a rolling field of winter wheat, vibrant green in the morning sun. A northern pintail hen, emaciated from almost a month of incubating her eggs, walks slowly in dappled sunlight beneath the thick canopy. Behind her, following in a ragged line, stumble eight downy ducklings, the product of a nest initiated among rows of grain stubble and rapidly growing wheat seedlings. Ahead lies the promise of a new generation of prairie pintails.